add numerical recipes library

2025-09-12 18:55:25 +09:00
parent d4dff245bd
commit 2c75620ec9
1344 changed files with 63869 additions and 0 deletions
--- a/lib/nr/cpp/recipes/ran4.cpp
+++ b/lib/nr/cpp/recipes/ran4.cpp
@@ -0,0 +1,25 @@
+#include "nr.h"
+
+DP NR::ran4(int &idum)
+{
+#if defined(vax) || defined(_vax_) || defined(__vax__) || defined(VAX)
+	static const unsigned long jflone = 0x00004080;
+	static const unsigned long jflmsk = 0xffff007f;
+#else
+	static const unsigned long jflone = 0x3f800000;
+	static const unsigned long jflmsk = 0x007fffff;
+#endif
+	unsigned long irword,itemp,lword;
+	static int idums = 0;
+
+	if (idum < 0) {
+		idums = -idum;
+		idum=1;
+	}
+	irword=idum;
+	lword=idums;
+	psdes(lword,irword);
+	itemp=jflone | (jflmsk & irword);
+	++idum;
+	return (*(float *)&itemp)-1.0;
+}